This proposal is for a Visual Sonics Vevo 2100 Imaging system. This instrument will be housed in the Cardiovascular Physiology Core facility at the University of Pennsylvania Translational Research Center (TRC). This Cardiovascular Physiology Core was created 5 years ago in an effort to bring clinically relevant analysis of cardiovascular physiology to investigators using mouse genetic models to understand human cardiovascular disease. It is a highly specialized and utilized core facility that performs echocardiography and vascular ultrasonography on mice from the earliest stages of development (E10.5 in utero) to maturity. Manned by a fully trained human fetal echo cardiographer, the goal of this core is to apply the same type and level of physiologic analysis to mouse genetic models that is used daily in the assessment of patients with complex cardiovascular diseases. The size and breadth of cardiovascular investigation at Penn has made this core a highly used and essential service for the institution. Its tight focus and the hig level training and expertise of the core has resulted in many new cardiovascular discoveries in mice that are pertinent to human diseases and added value to many genetic models created by NIH-funded investigators at Penn. The Cardiovascular Physiology Core presently uses a first generation Visual Sonics machine that provides basic imaging but lacks color Doppler and linear array technology, technical features that are essential to identify the type of cardiovascular defects observed daily in the clinic in prenatal and postnatal mice. The goal of this proposal is to replace this machine with one capable of providing imaging and flow data on a level commensurate with that used in our analysis of human patients to fully investigate and exploit sophisticated mouse genetic models of cardiovascular disease at Penn.